What We’re Learning From The James Webb Space Telescope

IRA FLATOW: This is Science Friday. I’m Ira Flatow.

FLORA LICHTMAN: And I’m Flora Lichtman. For the rest of the hour, ah, a universal palate cleanser. Think of this next segment as Science Friday’s happy hour?

IRA FLATOW: Oh, yeah.

FLORA LICHTMAN: Happy 20 minutes?

IRA FLATOW: At least.

FLORA LICHTMAN: TGIF, Ira.

IRA FLATOW: Absolutely. Because we’re going to be spending the rest of the hour talking about the latest from the James Webb Space Telescope. So much interesting stuff coming out of that research. Some of the discoveries coming from its observations. I mean, what do you want to know? What do you want to know about the Webb Telescope? Give us a call. Our number, 877-4SciFri. 877-472-4374.

And here to field your questions is Macarena Garcia Marin. She is an astrophysicist, an instrument scientist at the European Space Agency. She’s also Deputy Project Scientist at the Webb Space Telescope, based at the Space Telescope Science Institute, famously in Maryland. Welcome to Science Friday.

MACARENA GARCIA MARIN: Thank you. Thank you for having me.

IRA FLATOW: Let’s talk about this, because there’s so many really interesting things going on. So much exciting news. Let’s start with the news this week of this super old galaxy. I mean, to me it was mind blowing. Was it mind blowing?

MACARENA GARCIA MARIN: It was mind blowing to me, yes.

IRA FLATOW: Tell me why that is.

MACARENA GARCIA MARIN: Because we’re talking about galaxies that existed about 280 million years after the big bang. That’s nothing.

FLORA LICHTMAN: It’s like a baby galaxy.

MACARENA GARCIA MARIN: It’s like a baby galaxy.

IRA FLATOW: So they discovered this galaxy going way back in time.

MACARENA GARCIA MARIN: Way back in time. And let’s remember, the universe is about 13.8 billion years with a B. So this is a baby galaxy. And for a baby galaxy, it has had the time to actually have stars and reaching the galaxy and producing some additional chemical elements on top of hydrogen and helium. So it’s really, really a fast way of growing up.

IRA FLATOW: How old should it be to make those things instead of what it is now? What would you expect the age to be?

MACARENA GARCIA MARIN: I mean, it depends on when they start being. So stars, they can last, depending on their mass, they can last between millions and billions of years. But we don’t really how these very first stars were. They may have been thousands of times bigger than the sun.

IRA FLATOW: So why is your head exploding?

[LAUGHTER]

MACARENA GARCIA MARIN: Because this is really why we launched the James Webb Space Telescope. The primary science [? goals ?] was to observe these very first galaxies and very first stars. And actually this is the oldest we have confirmed with spectra, which is like the fingerprint or the DNA of the galaxy. So you decompose the light and can really make sure how old that galaxy is. But there are candidates that are based on imaging that are even older.

IRA FLATOW: There are older ones?

MACARENA GARCIA MARIN: Yeah, they are only candidates. They are not confirmed, because they are only based on imaging. But those galaxies, it’s very interesting, because they have been observed with Webb by using gravitational lensing. So that is nature helping us by enlarging galaxies that are really far away. So these galaxies are fainter. And the researchers, they think that probably they are the progenitors of these other galaxies we are seeing that are brighter and slightly closer. So it is mind blowing.

IRA FLATOW: So what is it here? Do we have to rewrite the laws of physics, or do we have to rewrite how we think galaxies form?

MACARENA GARCIA MARIN: I think we have to rewrite how we think galaxies form at that time of the universe. So the things like the big bang, the cosmological theories we have, they still hold. But we need to make adjustments to really understand how the galaxies form. It’s like the chicken and egg thing. Is it first the stars? Is it the black hole? How does this all come together?

FLORA LICHTMAN: Did these findings make us rethink anything about our own galaxy?

MACARENA GARCIA MARIN: I think what is making us rethink is if you go closer to us, still in a very young universe, we already see galaxies with spiral arms and even with bars. So to me, that’s also a surprise that in such an old universe, we already have those structures that take millions of years and billions of years to take place. So in that sense, yes, it is really making us rethink how long do you need to make those structures.

IRA FLATOW: Do you have any idea on that? Can you give us a little bit of a hint?

MACARENA GARCIA MARIN: We know, for instance, that bars, at least there is one galaxy that we have seen with Webb that has a bar when the universe was about 2 billion years old. Very early still.

IRA FLATOW: Yeah, but these are much earlier, right, these galaxies?

MACARENA GARCIA MARIN: Oh, yeah. The first one we were talking about, they are really babies. They are bold and bright. Yeah.

FLORA LICHTMAN: Let’s go to the phones. Let’s go to V in Ventura, California. Hi, V.

AUDIENCE: Hi. I’m on Science Friday?

FLORA LICHTMAN: You’re on Science Friday. Go ahead.

AUDIENCE: Awesome, yes. I had a question. As of recently, the James Webb Telescope found that there was kind of a void around our Milky Way Galaxy. I was wondering if you had any sort of insight into this, if maybe it’s a possible black hole that we’re going towards, or if it’s maybe some sort of dark matter we don’t about.

FLORA LICHTMAN: A void around our Milky Way Galaxy. Have you heard anything about this?

MACARENA GARCIA MARIN: Honestly not. But you’ve mentioned the black– you mentioned black holes and you’ve mentioned dark matter. So in both areas, Webb is also contributing. At the center of our own galaxy, there is a supermassive black hole. Millions and millions of mass in there and with stars circling around, the material circling around. So we’re looking into that with Webb. Not only the surrounding of the black hole, but all the structures around it and how that impacts the environment.

And when it comes to dark matter, we are also seeing things like gravitational lensing. How does the– so gravitational lensing is a situation where you have, for instance, a cluster of galaxies that are really, really massive. They are so big and so massive that they bend the light around. So when you do the calculations, you find out that there is actually a mass missing. So that means there is something like dark matter that you don’t see, but you know it’s there because it affects the light. So in that sense, yes.

IRA FLATOW: Do you think that dark matter has anything to do with the formation of these mystery galaxies that you’ve just discovered?

MACARENA GARCIA MARIN: I don’t know. That’s a good question.

FLORA LICHTMAN: This is one of Ira’s favorite topics.

MACARENA GARCIA MARIN: I love that. Yeah. Well, the truth is that there are many things we still don’t understand.

IRA FLATOW: I’m glad to hear you say that. Because a lot of people think science knows everything.

MACARENA GARCIA MARIN: No, we don’t. No. But that’s a good thing, because that means that we still have many, many questions that need to be answered. So we need more data and more generations of scientists really looking into this.

IRA FLATOW: And I’ve had, when we’ve talked about this before, I’ve had scientists say, you know, I like the chase more than the discovery.

MACARENA GARCIA MARIN: Yeah, exactly. The chase is great. And actually, before launching Webb, every other scientist you would ask, they would be excited about the surprises and it’s given us many.

FLORA LICHTMAN: What are you chasing?

MACARENA GARCIA MARIN: Me personally? I’ve been chasing following up with what she was asking, the center of our own galaxy. Actually, we got data very recently on some structures around the black hole. So I’m very excited looking into that.

FLORA LICHTMAN: Are they interesting? What are you finding?

MACARENA GARCIA MARIN: Yeah, well, we’re still looking at the data, so we’ll see about that.

IRA FLATOW: All right. Let’s go to the phones. San Antonio. Tali in San Antonio. Hi, welcome to Science Friday.

AUDIENCE: Hi. Thanks so much for taking my call.

IRA FLATOW: Go ahead.

AUDIENCE: My question is, I’m not sure if this is an active decision that was made, but how was it decided what direction the telescope was sent in, in space? How was that trajectory decided?

IRA FLATOW: Wow, yeah. And what direction to find these galaxies.

MACARENA GARCIA MARIN: You mean in which direction to find the galaxy. Oh, that’s a really good question. So first you go to the galaxies you already know they are there. And for that, we have what we call deep fields. For instance, the Hubble Space Telescope looked into these deep fields, and we knew there were galaxies that were perhaps about 400 million years old after the big bang.

So you look into the fields already have data, and you just observe during maybe 10 hours, and then you compare those images and do some tests to really understand if there are galaxies. And once you have candidates, then you go back and take spectra. That is you make a rainbow of that candidate. But yeah, the fields were fields that were already observed by telescopes like the Hubble Space Telescope.

FLORA LICHTMAN: It feels like we cannot talk about Webb without talking about exoplanets.

MACARENA GARCIA MARIN: I agree.

FLORA LICHTMAN: What is new and exciting there to you?

MACARENA GARCIA MARIN: New? Everything. Webb has opened up the field of exoplanets, which is great, because exoplanets didn’t even exist when Webb was conceived.

IRA FLATOW: Maybe we didn’t see them.

MACARENA GARCIA MARIN: Yeah, we hadn’t seen them.

IRA FLATOW: They might have been there.

MACARENA GARCIA MARIN: Sorry, they were there. You’re right. But as a science topic, quote unquote, we didn’t they were there. And now there are almost 6,000 of them. So yes, it’s a field that is really blossoming. Lots of discoveries, lots of new molecules. Observations of day side and night side. So it’s really, really exciting and it’s opening up a new field.

FLORA LICHTMAN: Well, there was this recent news that I think was linked to Webb about a biosignature.

MACARENA GARCIA MARIN: Correct.

FLORA LICHTMAN: On an exoplanet.

MACARENA GARCIA MARIN: Yes.

FLORA LICHTMAN: Burst our bubble or tell us what the real deal is.

MACARENA GARCIA MARIN: Oh, the real deal is that that’s a very bold claim.

FLORA LICHTMAN: Extraordinary claims.

MACARENA GARCIA MARIN: Extraordinary claims require extraordinary proof. So, of course, when that news came out, there was a lot of excitement. But then other scientists from the community actually looked at the data and they are concluding different things. So to confirm that claim, you would have to confirm the type of planet that it is.

And still it’s not clear if it’s something like a mini-Neptune or a hycean world that is a world that is water with a hydrogen atmosphere. So the type of planet. It’s still not clear if the detection is solid, and it’s still not clear if the molecules that are claimed are actually the ones they are, because they could be something else.

And the third thing is that even if all the other conditions are demonstrated, DMS, which is this molecule, you can also find it in comets and you can also find it in the interstellar medium. So many open questions.

IRA FLATOW: When you get up in the morning, what gets you excited about what you do?

MACARENA GARCIA MARIN: Everything, to be honest. I have to say, every day there is some new scientific discovery. Every day, there may be a new paper. Every day there is something that the community is excited about. And then part of the work is also to bring that message to the public. It’s not just about the science community.

IRA FLATOW: That’s what you’re here for.

MACARENA GARCIA MARIN: Exactly.

IRA FLATOW: And let’s go to the phones. Aaron in New Orleans. Hi, Aaron.

AUDIENCE: Yes, hi. Thanks so much for taking my call. I did have a question. I actually changed it to a much better one, if that’s OK.

IRA FLATOW: We’ll be the judge of that. Go ahead.

AUDIENCE: OK, thank you. Well, I wanted to ask your guest what is her opinion on the Oumuamua object? Do you think that this was something from intelligent life or do you think this was just some blip from another solar system that just happened into ours?

IRA FLATOW: Glad you changed your question. That was a good one. Yes.

MACARENA GARCIA MARIN: Yeah, that’s a really good question. Personally, I think it was a, quote unquote, “object or visitor” from outside of our solar system. As we were saying before, the claim of life or intelligence or anything like that, it requires really lots of proof, and we don’t have that.

IRA FLATOW: His original question, which I had, was whether the budget cuts are affecting your research and the research of astronomy and NASA and all the stuff that you do.

MACARENA GARCIA MARIN: So at this point, we don’t know. And that’s a question better addressed to NASA in terms of what–

IRA FLATOW: But you don’t feel it yourself at this point?

MACARENA GARCIA MARIN: At this point, no. What I feel and what I can really say is that the observatory is performing incredibly. The community is exciting and the science coming out of it, it’s really something worth pursuing every single day.

FLORA LICHTMAN: I think for the public and for someone like me, a lot of what I see from Webb are these beautiful images, and they bring me so much joy and so much pleasure. But I wondered for you, for astrophysicists, do you learn something by looking at the images? Or is it really just the data that underpins it that you’re interested in?

MACARENA GARCIA MARIN: We learn a lot from images. And actually often you first use the image to identify candidates of special galaxies or candidates of something and then you take a spectra. Because with imaging, you have much bigger field of view. You cover lots of space. But also the different colors you use to create these beautiful images, it’s a thing of– indivisible would be red and blue and green and all that. So you have infrared colors. These colors give you a lot of information. And all of these beautiful images you see, they are also used to do science with them.

FLORA LICHTMAN: So is it like a Where’s Waldo where you’re like, oh, look, there’s something in the corner that looks interesting? Let’s follow up.

MACARENA GARCIA MARIN: Yeah.

FLORA LICHTMAN: It is?

IRA FLATOW: Are people better at looking at the images than, let’s say, AI? I mean, if you got a bunch of people together to find stuff.

MACARENA GARCIA MARIN: I think there is a bit of both. I think the future of astronomy, I mean, the future of many missions is to have large, vast amounts of data. So there’s going to be some sort of machine learning techniques that can be applied for that. But behind that, I think personally you always need a person with a brain that can do the interpretation and actually the figuring out exactly what’s going on.

IRA FLATOW: And the Webb was specifically made to make these kinds of discoveries, right? What tools does it have to do that?

MACARENA GARCIA MARIN: It has four science instruments. They all operate on the infrared. So that’s the type of light we don’t see. But it’s really, really good to see cold objects and to peer through the dust and to see very distant objects. And we have about 75% of the time we do spectroscopy. So all of the four instruments have spectroscopic modes. We have a vast array of spectroscopy. And that means essentially we break up the light into a rainbow. And with that, you can really understand what’s going on. And they also do imaging. We do coronagraphy, which is a technique where you can block the light from a star, for instance, and see the planets around.

IRA FLATOW: Yeah, you need to do that.

MACARENA GARCIA MARIN: We do that as well. Exactly. So we do have a lot of scientific power behind all of the instruments.

IRA FLATOW: What’s happening– I already we’re talking about a successor to the Webb, the Roman Space Telescope. How would that be different from the Webb Telescope? What would it do differently?

MACARENA GARCIA MARIN: Roman will be different because it will look into a different wavelength. And also it’s a different concept. The Roman will do lots of surveys. Really large field of view, covering large portions of the sky.

IRA FLATOW: And what do you learn by doing that?

MACARENA GARCIA MARIN: Well, there’s going to be a lot of learning on transients. That is a transient is that you go to a region of the sky and observe it, and then you go back again and look for things that have changed. And that could be supernovae, that could be galactic nuclei, black holes active, et cetera.

IRA FLATOW: I see you’re not excited at all about this kind of work. I want to thank you for taking time to be with us today.

MACARENA GARCIA MARIN: Thank you.

IRA FLATOW: Macarena Garcia Marin is an astrophysicist and instrumental scientist for the European Space Agency, also Deputy Project Scientist for the Webb Space Telescope.

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